The southern portion of the Philippine Sea was found to be a possible prime location for marine renewable energy operations, in response to the expedition findings led by the University of the Philippines Marine Science Institute (UPMSI). It also found recent faults off eastern Palawan that were previously unmapped.
“The strong surface-to-deep temperature contrast observed within the southern Philippine Sea meets the thermal requirements for OTEC (Ocean Thermal Energy Conversion),” Dr. Charina Lyn Amedo-Repollo, lead of the Physical Commentary Laboratory, said in an announcement.
She noted that this means the world has high potential for continuous baseload renewable energy, and added that it could also support applications for desalination and seawater cooling.
The southern Philippine Sea was found to be ideal, because the critical 20-degree Celsius temperature difference between surface and deep water is already observed at a depth of only 200 meters, Ms. Repollo said.
That is shallower than what’s observed in lots of other tropical regions and other parts of the world, where the identical temperature difference is found at depths of as much as 1,000 meters or deeper.
The 20-degree Celsius temperature difference is good for efficiently operating OTEC, a renewable energy source that harnesses the temperature gap between warm surface waters and colder deep waters.
The findings said the unique condition of the southern Philippine Sea is on account of its open-ocean environment exposed to solar heating and influenced by large-scale ocean circulation.
The expedition was led by UPMSI and joined by scientists from the University of California, Santa Cruz and Mindanao State University–Naawan last December.
The team surveyed submarine volcanoes, energetic faults, internal waves, and areas for potential renewable energy within the Sulu Sea, Celebes Sea, and southern Philippine Sea.
Meanwhile, the researchers also found previously unmapped faults off eastern Palawan. One lies along the continental slope and shows about 10 meters of displacement, while one other extends about 20 kilometers along the projected extension of the Ulugan Bay Fault, cutting through sediment layers.
The findings align with earlier mapping by French and German scientists and should explain the magnitude-5.1 earthquake that struck Palawan on June 11, 2024, which the state seismologist linked to a known fault in the world.
Dr. Fernando P. Siringan, who led the Philippine team, said the structures is also tied to volcanic features within the Sulu Sea and stressed the necessity to reassess Palawan’s geology, especially it’s being regarded as a possible nuclear power plant site. — Edg Adrian A. Eva